Project: Barrabool Hills Shopping Centre Subject: Environmental Noise Addressee: Lascorp Development Group (Aust) Pty Ltd Issued To: Rob Harris Date: 4 September 2012 Reference: 13021-1 Prepared by: David Dolly (Director) B.App.Sc. M.A.A.S AAAC Member of the Association of Australian Acoustical Consultants
Acoustic Consulting Australia Pty Ltd. Page 2 of 13 CONTENTS 1.0 INTRODUCTION AND CONSULTING SCOPE... 3 2.0 PROJECT DETAIL AND NOISE SENSITIVE AREAS... 3 2.1 Noise Sensitive Locations... 3 3.0 STATUTORY NOISE LIMITS... 4 3.1 State Environment Protection Policy... 4 3.2 Noise Limits Calculated for this Site... 5 4.0 ENVIRONMENTAL NOISE CONTROL FOR PLANT & EQUIPMENT... 5 4.1 Refrigeration and Air Conditioning Condensers... 5 4.2 Air Conditioning & Refrigeration Compressors & Air Handling Unit... 8 4.3 Plant Room... 8 4.4 Plant Room Forced Ventilation... 9 4.5 Small Roof Mounted Fans... 9 4.6 Specialty Retail Shops - Air Conditioning Units... 10 5.0 ENVIRONMENTAL NOISE CONTROL FOR THE LOADING DOCK... 10 6.0 CONCLUSION... 12
Acoustic Consulting Australia Pty Ltd. Page 3 of 13 1.0 Introduction and Consulting Scope This report addresses the environmental noise control design requirements for the proposed retail development at the site at the corner of Province Boulevard and Stoneleigh Crescent in Barrabool. This report relates to this particular project and must not be applied to any other project without prior consultation with Acoustic Consulting Australia Pty Ltd as project designs and conditions can vary from project to project causing variation in acoustic performance and advice. This report addresses the range of noise sources that are associated with a proposed development of this type and makeup. These noise sources include operational noise from mechanical plant and equipment (ventilation, air conditioning and refrigeration) as well as noise form loading dock activities. 2.0 Project Detail and Noise Sensitive Areas The development involves the establishment of new buildings on the subject site as well as new plant and equipment to serve the major tenancy (a supermarket) and smaller specialty retail stores. Refrigeration and air conditioning plant is to be predominantly located at the roof level of the proposed buildings. Some of this equipment will operate on a 24 hour basis. Some of the equipment will be located on an open roof platform while other plant will be located in a dedicated plant room established at roof/mezzanine level. 2.1 Noise Sensitive Locations The site is located adjacent to residential and abuts a church to the east. Overall, the noise sensitive locations applicable to this evaluation are shown in the plan below. It is noted that the topography of this local areas varies significantly several residences will be or are elevated and will look across that the roof of the new store. Residences represented by R1 are at a lower elevation. Many of these residences are not existing; however construction in this well locality is underway. Residences represented by R2 will be at a similar or greater elevation; however this may vary depending on the location and type of future dwellings. This land is currently divided up for residential development.
Acoustic Consulting Australia Pty Ltd. Page 4 of 13 Diagram 1: Key Compliance Locations 3.0 Statutory Noise Limits 3.1 State Environment Protection Policy The Environment Protection Authority (EPA) set limits on the level of noise, which a commercial operation can emit to a residential area. The limits are determined by applying the procedures set out in the State Environment Protection Policy No. N-1 (SEPP N-1). The SEPP N-1 policy is technically applicable only in the Melbourne Metropolitan area; however this policy is used directly in rural town centres where ambient noise levels can be typical of a suburban setting.
Acoustic Consulting Australia Pty Ltd. Page 5 of 13 Based on our site assessment work we believe that it would be appropriate to apply the assessment methods described by the SEPP N-1 policy at this site. According to the SEPP N-1 Policy criteria, the noise level limits are calculated for each residence location individually and take account of the following factors. (i) (ii) (iii) The time of day (day, evening or night). The proportions of land zoned for residential, industrial and commercial use in the immediate local area. The background noise level, which would occur at the residence if activities associated with the commercial premises were not occurring. 3.2 Noise Limits Calculated for this Site In this case the permissible noise levels have been determined based on background noise measurements made in the area of the residences R1 to R3 and current land use zoning information obtained from the Department of Planning and Community Development. The permissible noise levels are as follows: Table 1 SEPP N-1 Permissible Noise Levels for R1, R2 and R3 Permissible Noise Level, db(a) Week Day (7am to 6pm) Saturday (7am-1pm) Weekday (6pm-10pm) Saturday (1pm-10pm) Sunday (7am-10pm) All Days (10pm-7am) 47 47 41 44 42 37 The permissible levels must be met outside the residential dwelling not greater than 10m from a habitable room. It should also be noted that the evening permissible noise limit calculation procedure is also applied to Saturday (1pm to 6pm) as well as Sunday and Public Holidays (7am to 6pm). 4.0 Environmental Noise Control for Plant & Equipment 4.1 Refrigeration and Air Conditioning Condensers Base on previous projects it is anticipated that up to 4 air-cooled condenser will be installed onto the roof mounted platform. It is understood that the platform be placed as shown below:
Acoustic Consulting Australia Pty Ltd. Page 6 of 13 Diagram 2: Location of Platform for Air Cooled Condensers Based on current supermarket design approaches it is anticipated that condenser fans will be driven by variable speed fans and that condensers will be Buffalo Trident LDV-NQ or LDV-SQ type or equivalent EC alternative. Preliminary calculations have been made based on three medium size condensers (8 fans) and one large condenser (10 fans). One of the medium size condensers is assumed for the air conditioning system. The following has been determined in relation to noise control: It is recommended that each refrigeration condenser meet a noise level specification of 62dB(A) at a reference distance of 3m when operating at full daytime load. This level would be achieved via model type and size selection. The noise rating must be reduced to 56dB(A) at 3m during the night period by capping the fan speed as required (likely to be 70% of full speed).
Acoustic Consulting Australia Pty Ltd. Page 7 of 13 Localised acoustic screening will be required along the west, south and east sides of the platform to achieve adequate noise control to all existing and future residences at and around locations R1 and R3. The mezzanine plant room can be used to achieve acoustic screening to then north (R2) provided that the top of the parapet wall is not less than 1200mm above the top of the tallest condenser. The plant room wall facing into the condenser deck area will require as sound absorptive finish to control sound reflection in the directions of R1 and R3. This lining will comprise of a 75mm thick acoustic insulation faced with a Melinex liner (20micron thick) and a perforated metal finish (11% open). The extent of this lining will be determined during the detailed design stages. The screens must extend to a height of not less than 1000mm above the top of the condenser fans. The screens must completely eliminate line of site to any condenser from any residence on the residential zone development. The anticipated screening extent is as follows: Diagram 3: Acoustic screening layout The main screens should be constructed as indicated in Diagram 3 (below). A 0.6mm custom orb could be used as an alternative to the cladding shown. Screens should extend down to the top of the platform; the platform can be open below the screen to allow air to flow to the condensers however the gap must be screened as shown schematically below:
Acoustic Consulting Australia Pty Ltd. Page 8 of 13 Diagram 4: Acoustic screening design concept Important: The height of the sub screen (below the platform) and the main screen will vary depending on direction and final platform elevation and this should be reviewed during the detailed design phase of the project. The sub screen must extend to a height of not less than 1000mm above the top of the platform. The screening system should be reviewed once the platform elevation and plant layout on the platform are confirmed. 4.2 Air Conditioning & Refrigeration Compressors & Air Handling Unit The air conditioning and refrigeration compressor units must be located inside the dedicated and acoustically treated plant room. It is anticipated that the air conditioning air handling unit would similar be placed in the plant room or on the external platform. 4.3 Plant Room For the purpose of this evaluation allowance has been made for a typical supermarket store compressor room and air handling unit installation including a plant room ventilation system. The plant room must include the following designs: Roof: Metal decking on thermal insulation with a 1x13mm plasterboard ceiling.
Acoustic Consulting Australia Pty Ltd. Page 9 of 13 Walls: Masonry (150 Precast Concrete Panel) or light weight system having a Sound Reduction index (R w ) of not less than R w 60. Doors: Any door between the plant room and the exterior must be a 40mm thick (solid timber core) doors fitted with acoustic seals rated to R w 30. Ventilation Openings to the plant room will require acoustic rating in the form of a 300 or 600mm thick acoustic louvre (depending on the final location). Louvres should be placed on the south side of the plantroom where escaping noise will be attenuated by the acoustic screening around the condenser deck. Some of the above may be varied during the design development phase as the noise control requirements will depend on the final layout of the plant room. 4.4 Plant Room Forced Ventilation The plant room ventilation fans should be located within the plant room. Roof mounted fans should not be used for the plant room at this site. The fans must meet a noise level rating of 62dB(A) at a distance of 1m outside the intake and/or exhaust point. A 1400mm long sound attenuator should be allowed for between each fan (supply and exhaust) and plant room envelope penetration. The acoustic performance of these sound attenuators will need to be determined during the detailed design phase once the fan selections are made. The intake and exhaust points could be via the east wall or roof but should not be via the west, north or south walls. 4.5 Small Roof Mounted Fans We refer to the following equipment times typically included in a supermarket: Chicken Hood O/A Fan Meat Prep O/A Fan Bakery Hood O/A Fan Stock room exh Fan x 2 Chicken Hood Exh Fan Meat Prep Exh Fan Bakery Hood Exh fan Donut Hood Exh Fan Dishwasher Exh Fan Seafood Prep Fan Toilet Exh Fan Small air conditioning condensers Liquor Air conditioning Unit
Acoustic Consulting Australia Pty Ltd. Page 10 of 13 The following are recommended to achieve compliance with noise limits: I. Fans may be located on or just above the store roof. II. III. IV. No fans should be within 15m of the northern, western or southern edge of the building. No fan should be placed on the loading dock roof. All fans must be reviewed upon selection to determine if dedicated sound attenuation is required (i.e. possible screening or repositioning). The selection of quieter slow running fans is recommended for this project. Fans will be required to meet a specification of 55dB(A) at a horizontal distance of 3m unless otherwise agreed based on fan position and acoustic screening provision. 4.6 Specialty Retail Shops - Air Conditioning Units These are anticipated to be small split system air conditioning systems that will operate only during normal business hours. Based on the proposed locations for the small stores and preliminary calculations it is likely that modest noise control (e.g. Acoustic screens) will be needed to control noise emitted to the south and west. A further review should be initiated once equipment details are available. 5.0 Environmental Noise Control for the Loading Dock The proposed location for the loading dock necessitates some very specific noise control recommendations: Recommendations: A. Deliveries to the store should be restricted to the period 7am to 10pm. No deliveries should be permitted outside these hours. This curfew would apply to all delivery trucks. B. The roof over the loading dock should be extended as indicated in diagram 5 (below). The roof will of traditional metal deck construction; however a sound absorptive soffit is recommended to the soffit. This insulation lining would be a 75mm thick, 24kg/m 3 density acoustic grade insulation with a perforated foil facing. The insulation must be exposed to the loading dock noise and so must not be clad over with plasterboard or similar. The northern wall along the loading dock/truck bay should extend to match the extent of the roof and must extend to the roof line. No gaps should be permitted between the head of this wall and the underside of the roof.
Acoustic Consulting Australia Pty Ltd. Page 11 of 13 Diagram 5: Loading Dock and Boundary Noise Control Treatment C. The all trucks (large and small) should be unloaded in the screened and roofed zone. D. It is recommended that a 2.1m tall acoustic fence be constructed along the northern site boundary as indicated above: This fencing height recommended is shown to scale in the diagram above. The fence should be constructed using the design shown in diagram 6 (below) and must take account of the following: The design must ensure that all gaps and openings are eliminated. The fence must remain gap and opening free over time. Alternative materials such as compressed cement sheet, masonry, thick plywood can all be considered for the acoustic fencing. Compressed cement sheeting should be at least 10mm thick and must be sealed at panel joints. Ply should be at least 30mm thick and must also be sealed at the joints.
Acoustic Consulting Australia Pty Ltd. Page 12 of 13 Diagram 6: Acoustic Fence Construction Note: Double storey residences should not be permitted at residential lots adjacent to the fence to avoid overlooking of the acoustic fence to the loading dock. If double storey residences are to be permitted then some acoustic upgrade work would be recommended for upstairs bedrooms/living spaces of the dwellings concerned. 6.0 Conclusion Environmental noise associated with air conditioning, refrigeration and ventilation plant proposed at the subject site has been considered.
Acoustic Consulting Australia Pty Ltd. Page 13 of 13 It is concluded that noise emissions can comply with the statutory noise limits described this report provided that the noise controls described are implemented. A curfew on delivery times is recommended along with acoustic fencing and roofing to attenuate truck movement noise and noise from truck unloading. David Dolly Acoustic Consulting Australia Pty Ltd